


Mistletoe Duplicity

by rayshant_bestopt



Category: Arrow (TV 2012), The Flash (TV 2014)
Genre: Alternate Universe - Canon Divergence, Barry Allen SCPD CSI, Christmas Party, M/M, and found out he was Arrow, but still totally in-love nerds, mistletoe kiss, never saved Oliver's life, no speedsters, ulterior motive Barry, ulterior motive Oliver
Language: English
Status: Completed
Published: 2017-12-26
Updated: 2017-12-26
Packaged: 2019-02-20 02:02:14
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,118
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13136805
Author URL: https://archiveofourown.org/users/rayshant_bestopt/pseuds/rayshant_bestopt
Summary: Barry is a Starling City CSI with a tiny bit of an obsession with the Arrow.  And Oliver Queen, who he's pretty sure is the same person.  What better Christmas gift for himself than getting proof of that at the Queen Consolidated Holiday Ball?Well, Oliver might have one idea...





	Mistletoe Duplicity

**Author's Note:**

  * For [blue_wonderer](https://archiveofourown.org/users/blue_wonderer/gifts).



> Olivarry Secret Santa fic for blue_wonderer (hope she likes it!)  
> Canon Divergent AU from Arrow 2.08 “The Scientist”, where Oliver’s secret is not revealed to Barry (and never gets hit with the particle accelerator, becoming the Flash), but Barry’s forensic work is used to help find and take down Cyrus Gold, leading him to transfer to Starling City Police Department as a “real” CSI.

“Wow, Felicity. This is…wow.” Barry could only gape as he stepped inside with his friend. He was wearing the best suit he owned, and yet he still felt incredibly underdressed at the Queen Consolidated Holiday Ball. If he didn’t have a reason for being here, he probably would seriously have considered backing out the way he came.

But he was here on a mission: he’d planted the seeds in his friend’s mind on their semi-regular coffee dates (not like _date_ -dates, but just a friendly, scheduled meeting between friends that liked to talk and drink coffee together), discussing how the SCPD didn’t really have a Christmas Party, and he’d missed tree trimming and eggnog with Joe and Iris (with fiance Eddie) this year. Felicity had taken the bait, offering to bring him as her plus-one to the QC company party, and, feeling confident, Barry had shined his loafers and headed downtown with his big plans: this was the day he was going to find undeniable proof confirming that Oliver Queen was Star City's one and only Vigilante. 

The party was being held in the actual QC building, which was perfect. Barry had memorized the building schematics he’d found online, had gone over scenario after scenario on different ways to access the top floor without drawing notice. He’d brought baggies and gloves and a tiny dusting kit so he could collect any evidence he’d found to bring back to the lab and compare it with the circumstantial evidence he’d been accumulating in his super-secret folder he’d stashed in his drawer since he’d arrived in Starling City eight months ago.

Not that he was planning on outing the man. He’d meant what he’d told Felicity when they’d first met, about believing the Vigilante-- the Arrow now-- could have, _would have_ found his mother’s killer. He'd kept a close eye on his activities from the start of his career, and he'd become more and more a hero in Barry’s mind. But Barry _was_ still a scientist, and his curiosity and thirst for answers to the unknown was inescapable.

After helping Felicity with The Acolyte, Barry couldn’t shake the thrill of working alongside the masked man (well, on the same case, at least). He had put in for a transfer, and Felicity had put in a good word for him with Captain Lance, landing him a job as a full CSI in Sterling. Felicity seemed to be pretty close to Lance, because she came by his lab on a few occasions to ask about circumstances for “hypothetical” crimes, that Barry would find in later reports to be connected to recently closed cases.

He knew it couldn’t be Felicity—considering the visual testimonies about the Arrow, she just was physically incapable of fitting the profile of the person behind the mask. However, Barry could easily see her as one of his partners, with her smarts and computer genius, and she said so herself that she spent an inordinate amount of time with Oliver Queen.

So Barry had spent a lot of time following the billionaire playboy. Not literally—that would be creepy, although Barry had met the man a few times besides the one case, probably making a fool of himself as he tried to make conversation. A difficult task, even if Barry didn't suspect him: Oliver Queen was a gorgeous specimen, with an unpredictable shift between intense rigidity and disarming charm that left Barry awkward and speechless (and maybe a little breathless). So he steered toward safer avenues, subtly asking Felicity about her work relative to him, and keeping tabs on QC website updates. And so the more time he spent in the Arrow's city, the bigger his Arrow Board grew, along with a folder of any evidence Barry managed to get his hands on.

And it all culminated in tonight’s event. The Arrow had been involved in stopping a robbery of a Starling National Bank armored truck, and Barry had been the CSI on the scene. He had found undeniable Arrow evidence, and now he just needed to get to the top suites and check out Oliver Queen’s office to find something to match the scene. As a forensic scientist, Barry knew people always took and left something wherever they went.

The plan was simple: go to the party with Felicity, don’t dance or do anything to make an idiot of himself, eventually lose Felicity in the crowd, and make his way up the elevators, where he’d have approximately twenty minutes before his friend would likely notice his absence to scour the room and bag every clump of dirt or hair he could get his tweezers on.

The first part of the plan seemed to be going well enough: Felicity smiled and told him he looked good, while she stunned in a floor length blue and silver dress. They went and got champagne, with both awkwardly shuffling back and forth when they realized they were under a sprig of hanging mistletoe, before Barry leaned forward with a shy smile to lightly peck her on the cheek.

“You two seem to be having fun.”

Barry’s face burned bright red as his eyes shifted to meet the scrutinizing gaze of none other than Oliver Queen.

“Oh, we weren’t—" Felicity’s hands flitted between them, and upward “—I mean, we _were_ , but not because we wanted—we aren’t--”

“We just realized someone hung some mistletoe,” Barry piped up, trying to help his friend, and half-wishing he hadn’t. Oliver’s inescapable stare had moved to fix on him instead, causing him to feel even more flustered than he had been previously. “You know, actually, in Norse mythology, the god Hodur was tricked by Loki into shooting an arrow made of mistletoe at his brother Baldur, which killed him, but the plant eventually came to represent a symbol of peace and friendship, so it was all good.” He nodded fervidly, eyes widening as the older man’s eyebrow arched quizzically. “Not to say people shooting arrows of mistletoe is why people kiss under it. _That’s_ actually a superstition left over from Victorian England. Otherwise I guess we'd kiss over arrows of the stuff. But nobody has arrows, right?” Crap, why didn’t he just hold up a flashing sign saying _I'm almost positive you’re the Arrow and am here tonight to prove it_? He needed to shut up. “Anyways, Merry Christmas, Mr. Queen.”

“Barry was just telling me that Starling City PD doesn't really have a holiday thing, so he was nice enough to be my plus-one to ours,” Felicity spoke up, saving Barry from himself. Oliver nodded, curtly, a small smile forming on his lips, and Barry gave him a nervous one in return.  


“Of course. Merry Christmas, Barry. And really, you can call me Oliver.” It wasn't the first time Oliver Queen had told him that, or had said Barry's name, but the younger man's face still lit up at the way he said it, cheeks warming as he watched Oliver’s lips twitch in response. Barry couldn't seem to help it.

“Merry Christmas, Oliver,” he repeated with a touch of awe, before dropping a nervous chuckle. After all, the two men had only spoken a few times since he’d moved here, and he’d always felt like an afterthought, as the billionaire-probably-masked-hero had always been seeking out Felicity when it happened.

“You know, Barry,” Felicity suddenly spoke up after a moment’s pause. “I forgot that I was expecting an update on a project I’ve been working on, and I left my phone in my clutch. Do you mind if I just—really fast?”

“What? Oh, sure.” Barry forced his gaze back to his friend as she gestured toward the coat check, forcing his mind back on the mission. Felicity leaving would give him the perfect opportunity to sneak out through the side entrance where the servers were headed to refill appetizer trays, and the room was getting crowded enough that it would take her awhile to realize he wasn’t in it.

“Great!” she enthused. “Oliver will be happy to stay with you, won’t you Oliver?”

Barry choked on the air he was breathing, eyebrows getting lost in the gelled brown shag of his hair as his eyes popped wide in surprise. He was supposed to be left awkward and alone during the party when Felicity left his side. He wasn’t supposed to be nodding dumbly as _Oliver-freaking-Queen_ agreed to stay with him without their mutual friend.

For a few minutes they just stood there, Barry completely unable to even fathom what to do. Firstly, he was _supposed_ to be getting to the office of the very man he was standing next to—he should be excusing himself to the bathroom, or getting a new glass of champagne. Something that would allow him to disappear into the crowd. However, he couldn’t bring himself to uproot his feet from the presence of his (unconfirmed) hero, looking insanely gorgeous in a tux to boot. But trying to think of small talk was becoming increasingly difficult. What did he know about Oliver Queen that would be appropriate to say? Nothing about the Arrow, that was for sure. He couldn’t imagine really bringing up anything that he and Felicity talked about either—a lot of their banter ended up devolving into mutual admiration of her employer’s physical form, or mocking his sometimes-overly serious demeanor, neither of which were probably good to discuss with the man in question. And while tabloids may have established Oliver Queen as bisexual, Barry wasn’t very good at flirting, or being charming at all, so that probably wouldn't happen.

“Would you like to dance?” Oliver finally suggested, gesturing to the floor, and Barry’s brain couldn’t figure out how to refuse. He wasn’t much of a dancer—in fact, it was on his swiftly-crumbling plan not to be anywhere _near_ the dance floor—but his fingers allowed one of Starling City’s Top 10 Most Eligible Bachelors to remove the flute from his grip; allowed calloused fingers to curl over his, and lead him out to the floor.

Barry managed to stammer out a quiet apology over the classical music, but Oliver just smiled gently and shook his head, squeezing the CSI’s hand in reassurance. “It’s really just about having a good lead,” he explained, slow and careful steps taking them in small circles. “So, how are you liking Starling City?”

Barry swallowed thickly, his mind fuzzy from the proximity of the very impressive musculature of the man that he’d sort of been obsessing over for the last year. “Um, it’s great. The SCPD is great, and Felicity is amazing, and…yeah.”

“Felicity said you’ve been feeling a little homesick with the holidays.”

Barry felt his cheeks flush slightly. “Well, I mean, a little. Between my work and my foster dad’s schedule, and Iris’ wedding planning, we haven’t had a lot of time to meet up all together these last few weeks. But we’re all going to see each other for New Year, so there’s that,” he added quickly, not wanting to sound too whiny.

“I get it, finding time to spend with your family is important,” Oliver agreed, and Barry dropped his eyes to the floor in embarrassment. He was sounding all put out over missing _one_ Christmas morning with his family, when Oliver had probably gone without any holidays period for _five years_. Not that he seemed to be judging Barry. In fact, his periphery noticed the older man actually tipping his head slightly to catch his gaze. “Did I say something wrong?”

“What? Oh, no…I just…I agree. Family is important,” Barry managed, offering the other man a shy smile, leading to a slightly easier back and forth about Christmas traditions between their respective families.

The music ended, and as Oliver guided them away from the floor, Barry was significantly less eager to leave than when they'd started. The younger man could already feel the missing pressure on the small of the back, and he regretted that he wasn’t more graceful that he could risk another dance without concern of stomping on Oliver’s feet. But crostinis passed by them on silver trays, and Barry took one, eager to have something to do with his hands.

He and Oliver talked a while longer, Barry gradually relaxing into a more natural conversation. Barry had been keeping track of the man’s activities, after all, so he was able to ask about certain events and projects that had happened, so long as he left out the mysterious appearance of the Arrow in nearby vicinities. Oliver obviously knew Captain Lance, leading to some small talk about people they both knew within the department. Apparently Felicity had brought him up quite a bit, which Barry imagined made some sense, since the mystery cases she came to him for were on Oliver’s behalf. But some of the things that Oliver brought up—his Grandma Esther’s special eggnog, the ugly sweater family tradition, his participation in snowman-building contests—were things that he couldn’t fathom Oliver Queen finding out from Felicity’s rambling and paying attention to. It was flooring and flattering simultaneously.

The clock chimed nearby, and Barry realized his window was closing in less than ten minutes. _Crap_. “Um, can you excuse me?” he sputtered, taking an awkward step backward as Oliver regarded him in confusion. “Sorry, just—just for a minute. I need to—I just need to use the…restroom. I’m so sorry. Just-- right back.”

He kept mouthing out apologies until his back had turned completely on the billionaire superhero, bumping awkwardly into a server’s tray, then grimaced and internally berated himself for being such an idiot as he walked as fast as he could without appearing to flee in embarrassment out the side door.

Barry raced toward the elevators, pounding on the button as his gaze flitted between his watch and the red light projecting the floor number leading down to the lobby. He quickly jumped inside as the doors finally opened, prompting the machine upward from the inside with the same impatient fervor.

His toes tapped loudly on the floor, and Barry hummed nervously along with the Christmas muzak as he tugged his vinyl gloves onto his hands in an attempt to keep himself from freaking out at the slow-moving numbers. The top floor finally opened, and the gangly scientist sprinted toward the far office door.

Ripping the kit out of his pocket, Barry immediately hunched over the floor, eyes darting around the carpet, the desk, the windows—anywhere that there could be clues. If this were a real crime scene, he’d have time to slowly sweep the area, to really scrutinize any potential evidence. Here, doing an illegal search and seizure right under the suspect’s nose, he had maybe five minutes before Oliver would notice his absence, if Felicity didn’t manage to come back and distract him first. He needed to find something _now_.

A fleck of dirt caught his eye on the floor, and Barry dropped to a squat next to Oliver Queen’s chair as he leaned in to investigate further. It was dark, like asphalt, which wasn’t incriminating in and of itself, but Barry bagged it anyways, ready to add it to the rest.

Another glint against the moonlight drew his attention, and Barry leaned closer, letting his knees touch carpet as he squinted at the floor to pluck up a fragment leaning against the leg. It was a metal, definitely, splintered from something sharp. With only his eyes, Barry couldn’t know anything with certainty, but in his heart, he knew—he just knew—that when he tested it, it would be a carbon-based projectile. Just like the arrow points the Vigilante used.

His heart soared.

“Barry?”

His heart stopped. His stomach dropped like lead as Barry snapped his head toward the entrance to Oliver Queen’s office…where none other than Oliver Queen himself was standing.

“Uhhhh…”

“Barry, what are you doing?” Careful steps moved closer, and Barry scrambled up from the awkward kneeling position to his feet, hastily stuffing his equipment into his suit pockets.

“I was, uh…” He hadn’t thought about an excuse in case he were caught. He especially hadn’t thought of an excuse if he were caught by _Oliver Queen_ , who he hadn’t considered even seeing tonight. _Crap_. “I was looking for a...pen,” he supplied, bright green eyes fixing on the utensil and lifting it triumphantly in his hand. “Found it?”

“You were looking for a pen...in my office?” Oliver’s stride drew him closer, and Barry’s panicked mind couldn’t help but notice how quiet and graceful the motion was. That was probably very useful in his vigilante work, being able to sneak up on bad guys. Or CSIs sneaking around his office.

“Yeah, well, Felicity—she asked me to…get it for her,” His story was getting worse by the second, but Barry didn’t really have any good alternatives coming to mind.

“Barry.” Oliver’s lip quirked slightly as he watched the other man. “I know what you’re doing.”

“You do?” _Oh shit_.

“Yeah.” He was actually smiling now, and Barry was terrified that he might die.

“Mr. Queen, I can explain—” Oliver Queen knew that he knew he was the Arrow, and he was smiling, and he was going to kill Barry before he could tell him that he was his hero. That seemed really weird, not to mention a little disappointing.

“ _Oliver_ , Barry—I told you. And, I mean, I guess I’d rather you did it downstairs, instead of sneaking all the way into my office, but I guess I understand wanting some privacy,” the billionaire continued, halting Barry’s thoughts in their tracks.

“I—what?”

The perfect blue orbs left him as they traveled upward, where a sprig of mistletoe was hanging off of the ceiling. Barry hadn’t even noticed. “You and Felicity set this up together, didn’t you?” he asked, shaking his head. “I knew she was plotting something when she insisted on putting it there.”

His eyes watched Barry expectantly, but his poor brain had just completely short-circuited. Oliver Queen was the Arrow, but he apparently _didn’t_ know Barry knew—he thought Barry was conspiring with Felicity to kiss him? And he was smiling—he _wanted_ Barry to kiss him?

“Uh, uh, yeah—I mean, I guess that was kind of suspicious, with Felicity being Jewish and all,” he stammered awkwardly, going along with the alibi Oliver provided.

“You know, she’s not particularly subtle about that either,” Oliver added with a chuckle. “But I guess I can appreciate the intent?”

Oliver was still staring at him pointedly, and it was then that Barry realized he was expecting Barry to come over and kiss him beneath the mistletoe. _Holy shit—Oliver Queen wanted him to kiss him beneath the mistletoe._

His feet floated over the carpet in a daze, and Barry honestly couldn’t think of anything. He just stared at those brilliant blue eyes and gulped as a tongue swept out and across pink lips, leave a light coat of spit.

_Holy shit._

When they stood directly before each other, Barry stopped, terrified to move any closer. His heart was pounding, and he was completely at a loss for thoughts, much less words. Oliver seemed to read something on his expression, however, because he smiled and leaned close, carefully pressing their lips against each other.

Barry only stayed frozen for a second longer, a soft moan suddenly escaping him as he leaned into the kiss because _Holy shit he was kissing Oliver Queen_. And not just a quick peck—he was pretty sure they’d passed three Mississippi’s by now. His body seemed to move of his own volition, because his hand was sliding up the other man’s suit jacket to rest on his broad shoulder, the other curling its fingers into the sandy blond hairs at the nape of his neck.

Oliver seemed equally enthusiastic as well. His hands grabbed at Barry’s coat, tugging him closer into the embrace as he deepened the kiss. Barry felt the older man’s tongue brush against the seam of his lip, and he opened instinctively, shivering as he began mapping out the inside of his mouth.

The kiss felt like forever, and yet not nearly long enough, with Oliver being the first to pull away, a sheepish but ridiculously charming smile on his face.

“Sorry, that was—”

“No!” _Too loud,_ Barry’s brain chastised him as it tried to recover from its time as a puddle of happy goop. Barry continued in a slight pant, “I mean, it was fine—great. I…thank you.” His face was burning up, and he half-wanted to jump out the window, half-grab the older man and kiss him again.

Oliver, for his part, just smiled fondly. “Merry Christmas, Barry.”

Barry’s brain was fried. “Merry Christmas, Mr.—Oliver,” he managed to correct himself, following the older man as he led him back to the elevators and downstairs where Felicity was waiting for him.

  
***  
  


The party had ended hours ago, and Oliver was now sitting alone in the foundry, staring into space. His fingers crept to his lips, touching them gently, recalling the lips eager against them earlier that night.

Heels clacked against the floor, and his hand fell back to his side. “You took care of it?” he asked.

“Dig found the folder, and the virus wiped out everything he had on his hard drive,” Felicity told him, a touch of shame coloring her tone. “I feel so bad—he’s going to be crushed on Monday.”

“It had to be done, Felicity,” Oliver reminded her, turning around to face the blonde as he pulled out a clump of crumpled up forensic baggies and handed them to her. “These too,” he added, keeping his face impassive as she eyed him sternly.

“I still think we could trust Barry with this,” she insisted grumpily for what must have been the hundredth time. “He already helps us out on a lot of cases, and he thinks the world of the Arrow--”

“We’d be putting him in danger, Felicity,” Oliver insisted. “And ourselves. If anyone else had found that folder—”

Felicity nodded, waving her hand. “I know, I know. I just hate lying to him. And—well, even if he can’t prove it, he knows it’s going to be us, Oliver. I don’t know how I’m going to be able to look at him at our coffee date.”

Oliver’s eyes dropped to his shoes, biting his lip at the thought of Felicity going to see Barry on Monday for coffee. There was an uneasy tug in his stomach at the thought, which he told himself was him being protective of his friend. “If you want, I could go,” he offered, eyes shifting back to her with a casual shrug. “Explain that you didn’t feel well, kind of get a sense of the situation.”

A stylized eyebrow quirked up at him over her glasses. “You would be willing to go talk to Barry the _day_ he finds out you were flirting with him as a distraction so we could destroy everything he’d found on the Arrow?’

“I’m willing to let him take out his anger on me instead of you,” Oliver countered, but Felicity’s expression didn’t look any less incredulous.

“What were you two doing while I was gone?” she asked, eyes widening as Oliver unconsciously swept his tongue over his lips, trying very hard not to think of finding Barry on his knees in front of Oliver's chair; of Barry's eyes wide and staring at him; of Barry's lips-- “Oh my god, Oliver—did you--?”

“No! I mean, we talked. Danced a little.” Felicity’s stare was relentless. “I found him up in the office, and I had to distract him so I could get into his pockets, so…”

“Oh my god, Oliver, you didn’t!” Oliver couldn’t quite tell if she was disappointed in him for taking advantage of her friend or pleased that he’d finally made a move (something she constantly hinted he should do, with as much time he spent looking into Barry Allen—for security purposes).

The back and forth following came at him a bit like a beat down as she seemed to be interrogating his intentions with her friend, but refused to let him back out of his offer now that she had the facts.

But Oliver had to admit later that, even when Barry “accidentally” spilled a scalding hot coffee on his lap a few days later before being willing to sit down at the table with him and talk for his entire lunch break, what turned out to be a very interesting coffee date with Barry Allen was probably the best Christmas gift he got that year.


End file.
